Explore chapters and articles related to this topic
Terms and Definitions
Published in Rick Houghton, William Bennett, Emergency Characterization of Unknown Materials, 2020
Rick Houghton, William Bennett
pH is a measurement of the concentration of hydronium ion (H+) in water. Water is H2O and has a neutral pH of 7. Occasionally, one water molecule will dissociate into H+ and OH−. This natural dissociation produces a concentration of one H+ for every 10,000,000 water molecules. There is also one OH– for every 10,000,000 water molecules.
Water Chemistry
Published in Frank R. Spellman, The Science of Water, 2020
Ionization: The formation of ions by splitting of molecules or electrolytes in a solution. Water molecules are in continuous motion, even at lower temperatures. When two water molecules collide, a hydrogen ion is transferred from one molecule to the other. The water molecule that loses the hydrogen ion becomes a negatively charged hydroxide ion. The water molecule that gains the hydrogen ion becomes a positively charged hydronium ion. This process is commonly referred to as the self-ionization of water.
Principles of Chemistry
Published in Arthur T. Johnson, Biology for Engineers, 2019
The hydronium ion is the common form of H+ in water. For bases, the general reaction is () YOH→Y++OH−
Optimization of liquid hot water pretreatment for extraction of nanocellulose crystal from South African waste corncobs
Published in Chemical Engineering Communications, 2023
Oluwagbenga A. Olawuni, Olawumi O. Sadare, Kapil Moothi
One of the leading green synthesis approaches is the liquid hot water technique, whereby no catalysts or chemicals are required to extract nanocellulose crystals. The method is cost-effective and environmentally friendly. The liquid hot water (LHW) treatment of biomass occurs at high temperatures (150–230 °C) to solubilize hemicellulose, disrupt the lignocellulosic matrix, and generate more reactive cellulose. The H bonds start to break down, allowing water to autoionize and form acid hydronium ions (H3O+), which can serve as the precursor of basic (OH−) or acidic (H3O+) catalysts. The hemicellulose fraction of biomass experiences depolymerization and cleavage of the acetyl group because its heterocyclic ether linkages are the most vulnerable. The reaction catalyzes hydrolysis by combining water’s hydrolytic characteristics with free organic acids’ activities (Hakim et al. 2022; Troy et al. 2013). Moreover, the concentration of H3O+ and OH− in neutral water is around 100 times higher than that of the normal at high temperatures. In this manner, the hot water will perform both acid and alkali catalysis and disrupt the glycosidic bonds to solubilize hemicellulose and slight delignification of waste biomass (Suriyachai et al. 2020; Cui et al. 2021).
Strength behavior of enzymatic cement treated clay
Published in International Journal of Geotechnical Engineering, 2021
A. Geethu Thomas, B. Kodi Rangaswamy
With the addition of a particular amount of terrazyme into the soil (negatively charged colloidal particles of fine-grained soil), a change in the adsorbed water layer surrounding the clay particles occurs. The adsorbed water contains metal ions with a positive charge such as sodium, potassium, aluminium, magnesium, etc. Primarily water molecules are dissociated into hydrogen ions (+) and hydroxyl ions (-), the former may again combine with water molecules to form hydronium ions, as shown in Figure 8. The positive charges from hydronium ions (+) or hydroxyl ions (-) combine with positively charged metal ions present in adsorbed water. Reduction in the electric charge of water molecules, pressure from negatively charged ions on positively charged metal ions in adsorbed water were observed due to the effect of Terrazyme addition. The metal ions are forced to move towards the free water from the adsorbed water layer and thereby break down of the electrostatic barrier occurs. The metal ions moved to the free water can be reduced or removed due to washing off/evaporation. This process will make the soil structure to a more friable matrix with an adsorbed water layer of thinner one (Raul Velasquez, Marasteanu, and Ray Hozalski 2005).
Development of electrochemical DPD molecular simulations for oil/water partitioning of organic acids at varying pH
Published in Journal of Dispersion Science and Technology, 2018
R. Skartlien, A. Bertheussen, S. Simon, J. Sjöblom
For high pH, the association between the hydroxyl ions and protons was accounted for, where the protons are donated mainly from the organic acid (and negligibly from hydronium that has a relatively smaller concentration at high pH). The hydroxyl is added together with a positively charged ion (e.g., Na+ for sodium hydroxide) to balance the charges. For low pH, the association between protons and water form hydronium, where the protons are donated from the organic and added acid. The charges from added protons were balanced by negative ions (e.g., Cl− for hydrocloric acid).